Mel B admitted it's "disappointing" Victoria Beckham wouldn't take part in a Spice Girls reunion.
The 43-year-old star will go back on the road for a stadium tour with bandmates Emma Bunton, Mel C and Geri Horner, but the fashion designer won't be joining them for the comeback shows.
Speaking to 'Entertainment Tonight', Mel said: "Yeah, it is disappointing, but it's not in some ways, because you have to be respectful of what she wants to do and you can't force anybody to do anything.
"But I still live in hope that she is going to join us, and she is a part of our band."
However, the 'Wannabe' singer admitted she'd be love to have a celebrity guest join the on stage during the tour for a special appearance.
Asked who could potentially step in, she added: "You're asking the wrong person. I'm just gonna say yes, of course, it can happen. I'd have to check in with the other girls first.
"I'm the one [that's] always thinking about stuff like that, always. And I'm the first one to say, 'Let's do this and we'll introduce Taylor Swift on one song or Adele or Katy Perry.' I think that's a great idea 'cause at the end of the day, it has to be a celebration."
It was previously revealed Victoria won't be joining the reunion as she is busy focusing on her family and fashion career but previously wished the girls well.
Earlier this month, after news of the reunion was revealed, Victoria wrote on Instagram: "Today marks a special day for the girls as they announce the first tour dates since we performed together in 2012!
"I won't be joining my girls on stage again but being in the Spice Girls was a hugely important part of my life and I wish them so much love and fun as they go back on tour next year.
"I know they will put on an amazing show and the fantastic fans past and present are going to have a wonderful time! X vb #spicegirls #friendshipneverends (sic)"
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